source: vis_dev/vis-2.3/src/cmd/cmdMisc.c

/**CFile***********************************************************************

  FileName    [cmdMisc.c]

  PackageName [cmd]

  Synopsis    [Variable table; miscellaneous commands related to the general
  system.]

  Author      [SIS]

  Copyright   [Copyright (c) 1994-1996 The Regents of the Univ. of California.
  All rights reserved.

  Permission is hereby granted, without written agreement and without license
  or royalty fees, to use, copy, modify, and distribute this software and its
  documentation for any purpose, provided that the above copyright notice and
  the following two paragraphs appear in all copies of this software.

  IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
  DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
  OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
  CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS ON AN
  "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO PROVIDE
  MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.]

******************************************************************************/

#include "cmdInt.h"
#include <errno.h>

static char rcsid[] UNUSED = "$Id: cmdMisc.c,v 1.59 2009/04/11 18:25:50 fabio Exp $";

/*---------------------------------------------------------------------------*/
/* Constant declarations                                                     */
/*---------------------------------------------------------------------------*/
/* The maximum length of an input line */
#define MAX_STR         32768


/*---------------------------------------------------------------------------*/
/* Variable declarations                                                     */
/*---------------------------------------------------------------------------*/
avl_tree *cmdAliasTable;
avl_tree *cmdFlagTable;

static boolean fileCreated;


/**AutomaticStart*************************************************************/

/*---------------------------------------------------------------------------*/
/* Static function prototypes                                                */
/*---------------------------------------------------------------------------*/

static int CommandTime(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandEcho(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandSetBddParameters(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandMemoryProfile(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandQuit(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandUsage(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandWhich(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandHistory(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandAlias(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandUnalias(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandSetVariable(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandUnsetVariable(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandHelp(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static int CommandSource(Hrc_Manager_t ** hmgr, int argc, char ** argv);
static void print_alias(char * value);
static char * command_alias_help(char * command);
static void FlushBuffers(int sigtype);

/**AutomaticEnd***************************************************************/


/*---------------------------------------------------------------------------*/
/* Definition of exported functions                                          */
/*---------------------------------------------------------------------------*/


/**Function********************************************************************

  Synopsis    [Looks up value of flag in table of named values.]

  Description [The command parser maintains a table of named values.  These
  are manipulated using the 'set' and 'unset' commands.  The value of the
  named flag is returned, or NIL(char) is returned if the flag has not been
  set.]

  SideEffects []

******************************************************************************/
char *
Cmd_FlagReadByName(
  char * flag)
{
  char *value;

  if (avl_lookup(cmdFlagTable, flag, &value)) {
    return value;
  }
  else {
    return NIL(char);
  }
}


/**Function********************************************************************

  Synopsis    [Updates a set value by calling instead of set command.]

  Description [Updates a set value by calling instead of set command.]

  SideEffects []

******************************************************************************/
void
Cmd_FlagUpdateValue(
  char * key, char * value)
{
  char *oldValue, *newValue;

  if (!key)
    return;
  if (value)
    newValue = util_strsav(value);
  else
    newValue = util_strsav("");

  if (avl_delete(cmdFlagTable, &key, &oldValue))
    FREE(oldValue);

  (void) avl_insert(cmdFlagTable, key, newValue);
}


/**Function********************************************************************

  Synopsis    [Deletes a set value by calling instead of unset command.]

  Description [Deletes a set value by calling instead of unset command.]

  SideEffects []

******************************************************************************/
void
Cmd_FlagDeleteByName(
  char * key)
{
  char *value;

  if (!key)
    return;

  if (avl_delete(cmdFlagTable, &key, &value)) {
    FREE(key);
    FREE(value);
  }
}


/**Function********************************************************************

  Synopsis    [Initializes the command package.]

  SideEffects [Commands are added to the command table.]

  SeeAlso     [Cmd_End]

******************************************************************************/
void
Cmd_Init(void)
{
  char *path;
  char *lib_name;


  cmdCommandTable = avl_init_table((int(*)(const void *, const void *))strcmp);
  cmdFlagTable = avl_init_table((int(*)(const void *, const void *))strcmp);
  cmdAliasTable = avl_init_table((int(*)(const void *, const void *))strcmp);

  Cmd_CommandAdd("alias", CommandAlias, 0);
  Cmd_CommandAdd("echo", CommandEcho, 0);
  Cmd_CommandAdd("help", CommandHelp, 0);
  Cmd_CommandAdd("quit", CommandQuit, 0);
  Cmd_CommandAdd("source", CommandSource, 0);
/*  Cmd_CommandAdd("undo", CommandUndo, 0); */
  Cmd_CommandAdd("set", CommandSetVariable, 0);
  Cmd_CommandAdd("unalias", CommandUnalias, 0);
  Cmd_CommandAdd("unset", CommandUnsetVariable, 0);
  Cmd_CommandAdd("time", CommandTime, 0);
  Cmd_CommandAdd("usage", CommandUsage, 0);
  Cmd_CommandAdd("history", CommandHistory, 0);
  Cmd_CommandAdd("which", CommandWhich, 0);
  Cmd_CommandAdd("set_bdd_parameters" , CommandSetBddParameters, 0);
  Cmd_CommandAdd("_memory_profile", CommandMemoryProfile, 0);
  fileCreated = FALSE;

  /* Program the signal of type USR1 to flush vis_stdout and vis_stderr */
#ifdef SIGUSR1
  (void) signal(SIGUSR1, FlushBuffers);
#endif

  /* set the default open_path */
  lib_name = Vm_VisObtainLibrary();
  path = ALLOC(char, strlen(lib_name) + 20);
  sprintf(path, "set open_path .:%s", lib_name);
  Cmd_CommandExecute(NULL, path);
  FREE(lib_name);
  FREE(path);
}


/**Function********************************************************************

  Synopsis    [Ends the command package.]

  Description [Ends the command package. Tables are freed, and the global
  error string is freed.]

  SideEffects []

  SeeAlso     [Cmd_Init]

******************************************************************************/
void
Cmd_End(void)
{
  avl_free_table(cmdFlagTable, (void (*)(char *))free, (void (*)(char *))free);
  avl_free_table(cmdCommandTable, (void (*)(char *)) 0, CmdCommandFree);
  avl_free_table(cmdAliasTable, (void (*)(char *)) 0, CmdAliasFree);
  if (cmdBackupHmgr != NIL(Hrc_Manager_t)) {
    Hrc_ManagerFree(cmdBackupHmgr);
  }
  error_cleanup();

  if (fileCreated == TRUE) {
    (void) fprintf(vis_stdout, "Purify has created a temporary file. The file");
    (void) fprintf(vis_stdout, " must be deleted.\n");
  }
}


/**Function********************************************************************

  Synopsis [Test that the given string is an integer. Returns 0 if string is
  not an integer, 1 if the integer is too big for int, and 2 if integer fits
  in int.]

  SideEffects [Sets the pointer value if the string is an integer small enough
  for int.]

******************************************************************************/
int
Cmd_StringCheckIsInteger(
  char *string,
  int *value)
{
  char *ptr;
  long l;

  errno = 0 ;
  l = strtol (string, &ptr, 0) ;
  if(*ptr != '\0')
    return 0;
  if (errno != 0)
    return 1;
  if ((l > MAXINT) || (l < -1 - MAXINT))
    return 1 ;
  *value = (int) l;
  return 2 ;
}


/*---------------------------------------------------------------------------*/
/* Definition of internal functions                                          */
/*---------------------------------------------------------------------------*/


/**Function********************************************************************

  Synopsis    [required]

  Description [optional]

  SideEffects [required]

  SeeAlso     [optional]

******************************************************************************/
void
CmdFreeArgv(int  argc,  char ** argv)
{
  int i;

  for(i = 0; i < argc; i++) {
    FREE(argv[i]);
  }
  FREE(argv);
}


/**Function********************************************************************

  Synopsis    [required]

  Description [optional]

  SideEffects [required]

  SeeAlso     [optional]

******************************************************************************/
void
CmdAliasFree(
  char * value)
{
  CmdAliasDescr_t *alias = (CmdAliasDescr_t *) value;

  CmdFreeArgv(alias->argc, alias->argv);
  FREE(alias->name);            /* same as key */
  FREE(alias);
}



/*---------------------------------------------------------------------------*/
/* Definition of static functions                                            */
/*---------------------------------------------------------------------------*/

/**Function********************************************************************

  Synopsis          [Implements the time command.]

  CommandName       [time]
  CommandSynopsis   [provide a simple elapsed time value]
  CommandArguments [\[-h\]\[-u\]]
  CommandDescription [Prints the processor time used since the last time
  command, and the total processor time used since VIS was started. <p>
  By default, the time reported is the CPU time spent executing instructions
  of the calling process and the time this process waited for children that
  terminated.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> -u
  <dd> Exclude child process time.
  </dl>]

  SideEffects        []

******************************************************************************/
static int
CommandTime(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  static long last_time_u = 0;
  static long last_time_c = 0;
  long time;
  int c;
  boolean excludeChildren = FALSE;

  util_getopt_reset();
  while ((c = util_getopt(argc,argv,"hu")) != EOF){
    switch(c){
    case 'h':
      goto usage;
    case 'u':
      excludeChildren = TRUE;
      break;
    default:
      goto usage;
    }
  }

  if (argc != util_optind) {
    goto usage;
  }

  if (excludeChildren) {
    time = util_cpu_time();
    (void) fprintf(vis_stdout,
                   "elapse: %2.1f seconds, total: %2.1f seconds\n",
                   (time - last_time_u) / 1000.0, time / 1000.0);
    last_time_u = time;
  } else {
    time = util_cpu_ctime();
    (void) fprintf(vis_stdout,
                   "elapse: %2.1f seconds, total: %2.1f seconds\n",
                   (time - last_time_c) / 1000.0, time / 1000.0);
    last_time_c = time;
  }
  return 0;

usage:
  (void) fprintf(vis_stderr, "usage: time [-h][-u]\n");
  (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
  (void) fprintf(vis_stderr, "   -u \t\texclude child process time\n");
  return 1;
}

/**Function********************************************************************

  Synopsis           [Implements the echo command.]

  CommandName        [echo]
  CommandSynopsis    [merely echo the arguments]
  CommandArguments   [\[-h\] &lt;args&gt;]
  CommandDescription [Echoes the arguments to standard output.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>]

  SideEffects        []

******************************************************************************/
static int
CommandEcho(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int i;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  for(i = 1; i < argc; i++) {
    (void) fprintf(vis_stdout, "%s ", argv[i]);
  }
  (void) fprintf(vis_stdout, "\n");
  return 0;

  usage:
  (void) fprintf(vis_stderr, "usage: echo [-h] string \n");
  (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
  return (1);
}

/**Function********************************************************************

  Synopsis    [Implements the set_bdd_parameters command.]

  SideEffects []

  CommandName [set_bdd_parameters]

  CommandSynopsis [Creates a table with the value of all the flags currently
  active in VIS and calls the function bdd_set_parameters with the manager of
  the current place in the hierarchy and the table.]

  CommandArguments [\[-h\]\[-s\]]

  CommandDescription [The command obtains the bdd manager of the current point
  in the hierarchy. Given this manager and the set of pairs (variable,value) of
  the VIS environment, the function sets specific BDD parameters to the given
  values. This command works in conjunction with print_bdd_stats.<p>

  Print_bdd_stats first prints a report of the parameters and statistics of the
  current bdd_manager. By using the command "set", the user may modify the
  value of any of the parameters of the underlying bdd package. The way to do
  it is by setting a value in the variable <tt>BDD.parameter name</tt> where
  <tt>parameter name<\tt> is the name of the parameter exactly as printed by
  the print_bdd_stats command. In order to "re-program" the underlying bdd
  package this command must be invoked.<p>

  Command options:<p>

  <dl>

  <dt> -h
  <dd> Print the command usage.

  <dt> -s
  <dd> Print the bdd parameter and statistics after the modification.

  </dl>
  ]

******************************************************************************/
static int
CommandSetBddParameters(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  Ntk_Network_t *network;
  boolean  showAfter;
  int      c;

  showAfter = FALSE;
  network = Ntk_HrcManagerReadCurrentNetwork(*hmgr);

  /*
   * Parse the command line.
   */
  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "hs")) != EOF) {
    switch (c) {
      case 'h':
        goto usage;
      case 's':
        showAfter = TRUE;
        break;
      default:
        goto usage;
    }
  }

  /* flatten_hierarchy and static_order must have been invoked already. */
  if (network == NIL(Ntk_Network_t)) {
    return 1;
  }
  if (!Ntk_NetworkReadMddManager(network)) {
    (void) fprintf(vis_stderr, "The MDD variables have not been ordered. ");
    (void) fprintf(vis_stderr, "Use static_order.\n");
    return 1;
  }

  /* Create the table of variable->value */
  bdd_set_parameters(Ntk_NetworkReadMddManager(network), cmdFlagTable,
                     vis_stdout);

  if (showAfter) {
    bdd_print_stats(Ntk_NetworkReadMddManager(network), vis_stdout);
  }

  return 0;  /* Everything okay */

usage:
  (void) fprintf(vis_stderr, "usage: set_bdd_parameters [-h] [-s]\n");
  (void) fprintf(vis_stderr, "   -h  print the command usage\n");
  (void) fprintf(vis_stderr, "   -s  print also the bdd statistics\n");

  return 1;
}

/**Function********************************************************************

  Synopsis    [Implements the _memory_profile command.]

  CommandName [_memory_profile]

  CommandSynopsis [It shows the amount of memory used by every pacakge.]

  CommandArguments [\[-f &lt;filename&gt;\] \[-h\] \[-p\] \[-u &lt;units&gt;\]]

  CommandDescription [This command intregrates the output from purify with a
  function map generated by a perlscript plus another perlscript to generate a
  memory profile of vis.<p>

  This command relies on the output of purify to a file to call the script
  "memoryaccount" and produce a summary of how much memory has been allocated
  by each package. Although this command may appear simple it requires the
  interaction of two scripts and three files, so special care should be taken
  when attempting to modify it.<p>

  Here is the way it works. The code in this command is conditionally compiled
  depending on the definition of the symbol <tt>PURIFY</tt>. If the symbol is
  not defined, the program prints a message notifying that the command is not
  operative in this executable. If <tt>PURIFY</tt> has been defined, there are
  certain things that are assumed. The executable has been linked with
  purify. The output of purify is being redirected to a file with name
  <tt>purify.log</tt>. The perl script <tt>memoryaccount</tt> is in
  <tt>$VIS/common/share</tt> and it is executable. There exists a file mapping
  function names to packages in the same place whose name is <tt>.fmap</tt>.<p>

  The command then calls <tt>purify_all_inuse()</tt> to force purify to dump to
  the file <tt>purify.log</tt> the information about the memory that is
  currently visible to the program. This memory is not the total memory
  allocated by the program since there may be leaked memory that is no longer
  accessible. A temporary file is created and the script <tt>memoryaccount</tt>
  is called to analyze the file <tt>purify.log</tt> and write in the temporary
  file the memory profile obtained from it. Once the script is done, the
  temporary file is dumped to <tt>vis_stdout</tt> and deleted.<p>

  Since most of the computation in this command is done by the pearlscript
  <tt>memoryaccount</tt>, for more information please refer to the message
  printed when the script is invoked with the option <tt>-h</tt>.

  Command options:<p>

  <dl>
  <dt> -f &lt;filename&gt;
  <dd> File to read the dump from. The default is purify.log. This option
  should be used if and only if the option <tt>-log-file</tt> has been used at
  the linking stage when building the executable.
  <dt> -h
  <dd> Print the command usage.
  <dt> -p
  <dd> Print also the packages that did not allocated any visible memory
  <dt> -u &lt;units&gt;
  <dd> Units to print the memory usage in. It may be "b" for
  bytes, "k" for kilobytes, "m" for megabytes and "g" for gigabytes. The default
  is bytes.
  </dl>
  ]

  SideEffects []

******************************************************************************/
static int
CommandMemoryProfile(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{

  int   c;
  char  options[128];
#ifdef PURIFY
  char  tmpFileName[128];
  FILE  *fp;
  char  command[256];
  char  *visDirectoryName;
  int   systemStatus;
#endif

  /*
   * Parse command line options.
   */
  options[0] = 0;
  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "f:hpu:")) != EOF) {
    switch(c) {
      case 'f':
        strcat(options, " -f ");
        strcat(options, util_optarg);
        break;
      case 'h':
        goto usage;
      case 'p':
        strcat(options, " -p ");
        break;
      case 'u':
        strcat(options, " -u ");
        strcat(options, util_optarg);
        break;
      default:
        goto usage;
    }
  }


#ifdef PURIFY
  /* Flag to remember that a file has been created by purify */
  fileCreated = TRUE;

  /* Obtain the name of a temporary file */
  tmpnam(tmpFileName);

  /* Kick purify to dump the data in the file */
  purify_all_inuse();

  /* Obtain the path to the perl script */
  visDirectoryName = Vm_VisObtainLibrary();

  /* Prepare the string to be sent to a shell */
  (void)sprintf(command, "%s/memoryaccount %s %s/.fmap ./.fmap >%s",
                visDirectoryName, options, visDirectoryName,
                tmpFileName);

  /* Effectively execute the perlscript */
  systemStatus = system(command);
  if (systemStatus != 0) {
    return 1;
  }

  fp = Cmd_FileOpen(tmpFileName, "r", NIL(char *), 1);

  /* Check if the open has been successful */
  if (fp == NIL(FILE)) {
    (void) fprintf(vis_stderr, "** cmd error: File %s was not found\n", tmpFileName);
    return 1;
  }

  /* Dump the contents of the result file in vis_stdout */
  while(fgets(command, 128, fp) != NIL(char)) {
    (void) fprintf(vis_stdout, "%s", command);
  }
  fclose(fp);

  /* Remove the temporary file */
#if HAVE_UNLINK
  unlink(tmpFileName);
#endif
#else
  (void) fprintf(vis_stderr, "** cmd error: Command not available: Vis has not been ");
  (void) fprintf(vis_stderr, "compiled with purify.\n");
#endif

  return 0;             /* normal exit */

  usage:
  (void) fprintf(vis_stderr, "usage: _memory_profile [-f <filename>] [-h] ");
  (void) fprintf(vis_stderr, "[-p] [-u <units>] <filenames>\n");
  (void) fprintf(vis_stderr, "   -f <file>\tFile to read the purify dump");
  (void) fprintf(vis_stderr, " from. The default is purify.log\n");
  (void) fprintf(vis_stderr, "   -h\t\tprint the command usage\n");
  (void) fprintf(vis_stderr, "   -p\t\tPrint also the packages that do not ");
  (void) fprintf(vis_stderr, " allocate any memory\n");
  (void) fprintf(vis_stderr, "   -u <units>\tUnits to print the memory usage");
  (void) fprintf(vis_stderr, " in. It may be b for bytes\n");
  (void) fprintf(vis_stderr, "     \t\tk for kilobytes, m for megabytes and ");
  (void) fprintf(vis_stderr, "g for gigabutes.\n");
  return 1;             /* error exit */
}


/**Function********************************************************************

  Synopsis          [Implements the quit command.]

  Description [A return value of -1 indicates a quick quit, -2 return frees
  the memory.]

  CommandName       [quit]
  CommandSynopsis   [exit VIS]
  CommandArguments  [\[-h\] \[-s\]]
  CommandDescription [Stops the program.  Does not save the current network
  before exiting.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> -s
  <dd> Free all the memory before quitting.
  This is slower, and is used for finding memory leaks.
  </dl>
  ]

  SideEffects        []

******************************************************************************/
static int
CommandQuit(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc,argv,"hs")) != EOF){
    switch(c){
      case 'h':
        goto usage;
      case 's':
        return -2;
      default:
        goto usage;
    }
  }

  if ( argc != util_optind){
    goto usage;
  }
  return -1;

  usage:
    (void)fprintf(vis_stderr, "usage: quit [-h] [-s]\n");
    (void)fprintf(vis_stderr, "   -h  print the command usage\n");
    (void)fprintf(vis_stderr, "   -s  frees all the memory before quitting\n");
    return 1;
}

/**Function********************************************************************

  Synopsis          [Implements the usage command.]

  CommandName       [usage]
  CommandSynopsis   [provide a dump of process statistics]
  CommandArguments  [\[-h\]]
  CommandDescription [Prints a formatted dump of processor-specific usage
  statistics. For Berkeley Unix, this includes all of the information in the
  getrusage() structure.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl> ]

  SideEffects        []

******************************************************************************/
static int
CommandUsage(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc,argv,"h")) != EOF){
    switch(c){
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc != util_optind){
    goto usage;
  }
  util_print_cpu_stats(vis_stdout);
  return 0;

  usage:
    (void) fprintf(vis_stderr, "usage: usage [-h]\n");
    (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
    return 1;
}

/**Function********************************************************************

  Synopsis          [Implements the which command.]

  CommandName       [which]
  CommandSynopsis   [look for a file called name]
  CommandArguments  [\[-h\] &lt;file_name&gt;]
  CommandDescription [Looks for a file in a set of directories
  which includes the current directory as well as those in the VIS path.
  If it finds it, it reports the path.
  The path is specified through the "set open_path" command in the .visrc.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> &lt;file_name&gt;
  <dd> File to be searched
  </dl>]

  SideEffects       []

  SeeAlso           [set]

******************************************************************************/
static int
CommandWhich(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  FILE *fp;
  char *filename;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc,argv,"h")) != EOF){
    switch(c){
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc-1 != util_optind){
    goto usage;
  }

  fp = Cmd_FileOpen(argv[1], "r", &filename, 0);
  if (fp != 0) {
    (void) fprintf(vis_stdout, "%s\n", filename);
    (void) fclose(fp);
  }
  FREE(filename);
  return 0;

  usage:
    (void)fprintf(vis_stderr,"usage: which [-h] file_name\n");
    (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
    return 1;
}


/**Function********************************************************************

  Synopsis          [Implements the history command.]

  CommandName       [history]

  CommandSynopsis   [list previous commands and their event numbers]

  CommandArguments  [\[-h\] \[&lt;num&gt;\]]

  CommandDescription [Lists previous commands and their event numbers.
  This is a UNIX-like history mechanism inside the VIS shell.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> &lt;num&gt;
  <dd> Lists the last &lt;num&gt; events.  Lists the last
  30 events if &lt;num&gt; is not specified.
  </dl><p>

  History Substitution:<p>

  The history substitution mechanism is a simpler version of the csh history
  substitution mechanism.  It enables you to reuse words from previously typed
  commands.<p>

  The default history substitution character is the `%' (`!' is default for
  shell escapes, and `#' marks the beginning of a comment). This can be changed
  using the "set" command. In this description '%' is used as the history_char.
  The `%' can appear anywhere in a line.  A line containing a history
  substitution is echoed to the screen after the substitution takes place.
  `%' can be preceded by a `\\' in order to escape the substitution,
  for example, to enter a `%' into an alias or to set the prompt.<br><p>

  Each valid line typed at the prompt is saved.  If the "history" variable
  is set (see help page for "set"), each line is also echoed to the history
  file.  You can use the "history" command to list the previously typed
  commands. <p>

  Substitutions: <p>

  At any point in a line these history substitutions are
  available.<p>
        <dl><dt>%:0   <dd>  Initial word of last command.</dl>
        <dl><dt>%:n   <dd>   n-th argument of last command.</dl>
        <dl><dt>%$    <dd>   Last argument of last command.</dl>
        <dl><dt>%*    <dd>   All but initial word of last command.</dl>

        <dl><dt>%%    <dd>   Last command.</dl>
        <dl><dt>%stuf <dd>   Last command beginning with "stuf".</dl>
        <dl><dt>%n    <dd>   Repeat the n-th command.</dl>
        <dl><dt>%-n   <dd>   Repeat the n-th previous command.</dl>
        <dl><dt>^old^new  <dd>       Replace "old" with "new" in previous command.
        Trailing spaces are significant during substitution.
        Initial spaces are not significant.</dl>  ]

  SideEffects        []

  SeeAlso            [set]

******************************************************************************/
static int
CommandHistory(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int i, num, lineno;
  int size;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc > 3) {
    goto usage;
  }
  num = 30;
  lineno = 1;
  for (i = 1; i < argc; i++) {
    if (argv[i][0] == '-') {
      if (argv[i][1] == 'h') {
        lineno = 0;
      }
      else {
        goto usage;
      }
    }
    else {
      num = atoi(argv[i]);
      if (num <= 0) {
        goto usage;
      }
    }
  }
  size = array_n(vm_commandHistoryArray);
  num = (num < size) ? num : size;
  for (i = size - num; i < size; i++) {
    if (lineno != 0) {
      (void) fprintf(vis_stdout, "%d\t", i + 1);
    }
    (void) fprintf(vis_stdout, "%s\n", array_fetch(char *, vm_commandHistoryArray, i));
  }
  return(0);

usage:
  (void) fprintf(vis_stderr, "usage: history [-h] [num]\n");
  (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
  (void) fprintf(vis_stderr, "   num \t\tprint the last num commands\n");
  return(1);
}




/**Function********************************************************************

  Synopsis          [Implements the alias command.]

  CommandName       [alias]

  CommandSynopsis   [provide an alias for a command]

  CommandArguments  [\[-h\] \[&lt;name&gt; \[&lt;string&gt;\]\]]

  CommandDescription [The "alias" command, if given no arguments, will print
  the definition of all current aliases.  <p>

  Given a single argument, it will print the definition of that alias (if any).

  Given two arguments, the keyword "name" becomes an alias for
  the command string "string", replacing any other alias with the
  same name.<p>

  Command options:
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> &lt;name&gt;
  <dd> Alias
  </dl>
  <dl><dt> &lt;string&gt;
  <dd> Command string
  </dl>

  It is possible to create aliases that take arguments by using the history
  substitution mechanism.  To protect the history substitution character `%'
  from immediate expansion, it must be preceded by a `\\' when entering the
  alias. <p>

  For example:<p>
  <pre>
   vis> alias read read_\\%:1 \\%:2.\\%:1
   vis> read blif lion
  </pre>
  will create an alias `read', execute "read_blif lion.blif".  <p>

  And...<p>
  <pre>
  vis> alias echo2 "echo Hi ; echo \\%* !"
  vis> echo2 happy birthday
  </pre>
  will print:<p>
  <pre>
  Hi
  happy birthday !
  </pre>

  CAVEAT: Currently there is no check to see if there is a circular
  dependency in the alias definition. e.g.<p>

  <pre>
  vis> alias foo "print_network_stats; print_network; foo"
  </pre>

  creates an alias which refers to itself. Executing the command "foo" will
  result an infinite loop during which the commands "print_network_stats"
  and "print_network" will be executed.<p>

   ]

  SideEffects        []

  SeeAlso            [unalias]

******************************************************************************/
static int
CommandAlias(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int i;
  char *key, *value;
  CmdAliasDescr_t *alias;
  avl_generator *gen;
  int status;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }


  if (argc == 1) {
    avl_foreach_item(cmdAliasTable, gen, AVL_FORWARD, &key, &value) {
      print_alias(value);
    }
    return 0;

  }
  else if (argc == 2) {
    if (avl_lookup(cmdAliasTable, argv[1], &value)) {
      print_alias(value);
    }
    return 0;
  }

  /* delete any existing alias */
  key = argv[1];
  if (avl_delete(cmdAliasTable, &key, &value)) {
    CmdAliasFree(value);
  }

  alias = ALLOC(CmdAliasDescr_t, 1);
  alias->name = util_strsav(argv[1]);
  alias->argc = argc - 2;
  alias->argv = ALLOC(char *, alias->argc);
  for(i = 2; i < argc; i++) {
    alias->argv[i-2] = util_strsav(argv[i]);
  }
  status = avl_insert(cmdAliasTable, alias->name, (char *) alias);
  assert(!status);  /* error here in SIS version, TRS, 8/4/95 */
  return 0;

  usage:
    (void) fprintf(vis_stderr, "usage: alias [-h] [command [string]]\n");
    (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
    return (1);
}


/**Function********************************************************************

  Synopsis           [Implements the unalias command.]

  CommandName        [unalias]
  CommandSynopsis    [remove the definition of an alias.]
  CommandArguments   [\[-h\] &lt;alias_names&gt;]
  CommandDescription [Removes the definition of an alias.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> &lt;alias_names&gt;
  <dd> Aliases to be removed
  </dl>]

  SideEffects        []

  SeeAlso            [alias]

******************************************************************************/
static int
CommandUnalias(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int i;
  char *key, *value;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc < 2) {
    goto usage;
  }

  for(i = 1; i < argc; i++) {
    key = argv[i];
    if (avl_delete(cmdAliasTable, &key, &value)) {
      CmdAliasFree(value);
    }
  }
  return 0;

  usage:
    (void) fprintf(vis_stderr, "usage: unalias [-h] alias_names\n");
    (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
    return 1;
}


/**Function********************************************************************

  Synopsis          [Implements the set command.]

  CommandName       [set]

  CommandSynopsis   [set an environment variable]

  CommandArguments  [\[-h\] \[&lt;name&gt;\] \[&lt;value&gt;\]]

  CommandDescription [ A variable environment is maintained by the command
  interpreter.
  The "set" command sets a variable to a particular value, and the
  "unset" command removes the definition of a variable.
  If "set" is given no arguments, it prints the current value of all variables.<p>

  Command options:<p>
  <dl> <dt> -h
  <dd> Print the command usage.
  </dl>
  <dl> <dt> &lt;name&gt;
  <dd> Variable name
  </dl>
  <dl> <dt> &lt;value&gt;
  <dd> Value to be assigned to the variable.
  </dl>

 <p>
  Interpolation of variables is allowed when using the set command. The
  variables are  referred to with the prefix of '$'. So for example, the following
  can be done to check the value of a set variable:<br>
  <code>
  vis> set foo bar <br>
  vis> echo $foo <br>
  bar <br>
  </code>

  The last line "bar" will the output produced by vis.<p>

  Variables can be extended by using the character ':' to concatenate
  values. For example : <br>
  <code>
  vis> set foo bar <br>
  vis> set foo $foo:foobar <br>
  vis> echo $foo <br>
  bar:foobar <br>
  </code>
  The variable <code> foo </code> is extended with the value <code>
  foobar </code>. <p>

  Whitespace characters may be present within quotes. However, variable
  interpolation lays the restriction that the characters ':' and '/' may
  not be used within quotes. This is to allow for recursive interpolation.
  So for example, the following is allowed<br>
    <code>
  vis> set "foo bar" this <br>
  vis> echo $"foo bar"<br>
  this <br>
  </code>
  The last line will be the output produced by vis. <br>
  But in the following, the  value of the variable <code> foo/bar </code>
  will not be interpreted correctly:<p>
  <code>
  vis> set "foo/bar" this <br>
  vis> echo $"foo/bar" <br>
  foo/bar <br>
  </code>
  If a variable is not set by the "set" command, then the variable is returned
  unchanged.
  <p>

  Different commands use environment information for different purposes.
  The command interpreter makes use of the following parameters:<p>

 <dl>
 <dt><b>autoexec</b>
 <dd>     Defines a command string to be automatically executed after every
           command processed by the command interpreter.
           This is useful for things like timing commands, or tracing the
           progress of optimization.
</dl>


 <dl><dt><b>open_path</b>
 <dd>      "open_path" (in analogy to the shell-variable PATH) is a list of
           colon-separated strings giving directories to be searched whenever
           a file is opened for read.  Typically the current directory (.) is
           first in this list.  The standard system library (typically
           $VIS_LIBRARY_PATH) is always implicitly appended to the current path.
           This provides a convenient short-hand mechanism for reaching
           standard library files.
 </dl>
 <dl><dt> <b>vis_stderr </b>
 <dd>   Standard error (normally stderr) can be re-directed to a file
           by setting the variable vis_stderr.
 </dl>

 <dl><dt>  <b>vis_stdout</b>
 <dd>           Standard output (normally stdout) can be re-directed to a file
           by setting the variable vis_stdout.
 </dl>

 Building MDDs for the network makes use of following setting:
 <dl><dt> <b>partition_method</b>
 <dd> This parameter is used to select the method for creating the
 partition.  The vertices of a partition correspond to the
  combinational inputs, combinational outputs, and any intermediate nodes used.  Each vertex has a multi-valued
  function (represented by MDDs) expressing the function of the corresponding
  network node in terms of the partition vertices in its transitive fanin.
  Hence, the MDDs of the partition represent a partial collapsing of the
  network. The possible values of partition_method are:
  <dl>
  <dt> <b>inout</b>
  <dd>Expresses the combinational outputs in terms of the
  combinational inputs. This is the default partitioning method.

  <dt> <b>total</b>
  <dd> The partition built is isomorphic to the combinational
  part of the network.  The function of each node is expressed in terms of its
  immediate fanins.

  <dt> <b>frontier</b>
  <dd> The partition built contains the combinational part of the
  network as well as vertices corresponding to some intermediate
  nodes. These vertices are generated to control the MDD sizes of the
  combinational outputs. The number of intermediate variables can be
  controlled by the parameter "partition_threshold". The method
  "inout" and "total" are special cases of this method (corresponding
  to a partition_threshold of infinity and 0 respectively).

  </dl>
  </dl>
 <dl><dt> <b>partition_threshold</b>
 <dd> This parameter is used in
 conjuction with the selection of "frontier" as partition method. This
 determines the threshold at which a new MDD variable is created in
 the partition.
 </dl>

 Image computation makes use of following settings:

 <dl>
   <dt><b>image_method</b>
   <dd> The "image_method" parameter is used to control the image method used
   in various symbolic analysis techniques. Currently, two image methods are
   implemented. Use "set image_method &lt;method&gt;" to choose the appropriate
   method.

   <dl>
     <dt><b>monolithic</b>
     <dd> This is the most naive approach possible. However, this method is not
     suitable for circuits with more than 20 latches.

     <dt><b>tfm</b>
     <dd> This is the pure transition function method. This method is supposed
     not to be used in general fixpoint computations. Approximate traversal is
     an application of this method. Basically this method is made as a part of
     hybrid method. For more detailed options, see the help of
     print_tfm_options command.

     <dt><b>hybrid</b>
     <dd> This is a hybrid method combining transition relation and function
     methods. Transition relation method is based on conjunction of partitioned
     transition relation, whereas transition function method is based on
     splitting on an input or output variable recursively.  The hybrid method
     choose either splitting or conjunction at each recursion dynamically using
     the dependence matrix. For details, refer to the paper "To split or to
     Conjoin: The Question in Image Computation" by In-Ho Moon, James Kukula,
     Kavita Ravi, and Fabio Somenzi, DAC'00. Also for more detailed options,
     see the help of print_hybrid_options command.

     <dt><b>iwls95</b>
          <dd> This technique is based on the early variable quantification and
     related heuristics of Ranjan, et al.  "Efficient BDD Algorithms for FSM
     Synthesis and Verification", IWLS 1995. First, from the given multivalued
     functions, bit level relations are created. These relations are then
     clustered based on the value of threshold value controlled by
     <b>image_cluster_size</b> parameter. Next the relations are ordered for
     early variable quantification. This ordering is controlled by the
     parameters <b>image_W1, image_W2, image_W3,</b> and <b>image_W4</b>.

     <dt><b>mlp</b>
     <dd> This technique is based on minimizing the variable lifetime
     in the conjunctions of the partitioned transition relation. The
     method is called MLP (Minimal Lifetime Permutation). For details,
     refer to the paper "Border-Block Triangular Form and Conjunction Schedule
     in Image Computation" by In-Ho Moon, Gary Hachtel, and Fabio Somenzi,
     FMCAD'00. Also for more detailed options, see the help of
     print_mlp_options command.
   </dl>


   <dt><b>image_farside_method</b>
   <dd> This parameter is used in conjunction with the selection of
   <b>iwls95</b>, <b>mlp</b>, or <b>linear</b> as the
   <b>image_method</b>. When the value is 1, the compositional far
   side image computation approach is enabled; when the value is 0,
   this feature is disabled (default).

   <dt><b>image_cluster_size</b>
   <dd> This parameter is used in conjunction with the selection of
   <b>iwls95</b> as the <b>image_method</b>. The value of this parameter is
   used as threshold value for creating clusters. The default value of this
   parameter is 5000 which has been empirically proved to be an optimal value.

   <dt><b>image_W1, image_W2, image_W3, image_W4</b>
   <dd> These parameters are used in conjunction with the selection of
   <b>iwls95</b> as the <b>image_method</b>. They control the weights
   associated with various factors in ordering the clusters. The default values
   are 6, 1, 1, and 2 respectively. For a detailed description of these
   parameters, please refer to the paper in IWLS'95 proceedings.

   <dt><b>image_verbosity</b>
   <dd> Sets the verbosity mode (0 minimum to 4 maximum), for the image method
   <b>iwls95</b>.<p>

  <dt>image_minimize_method  &lt;method&gt;
  <dd> Sets a minimization method to minimize the transition relation or an
  image/preimage computaion with a set of dont-care states.  <p>
  Methods:
  <code> 0 </code>: restrict (default). <p>
  <code> 1 </code>: constrain <p>
  <code> 2 </code>: compact (currently supported by only CUDD) <p>
  <code> 3 </code>: squeeze (currently supported by only CUDD) <p>

  <dt>scc_method &lt;method&gt;
  <dd> Sets the symbolic method to enumerate strongly connected components
  (SCCs). Symbolic SCC enumeration is the core computation in LTL and
  fair-CTL model checking.
  <p> Methods: <code> lockstep </code>: the O(nlogn) time LockStep
  algorithm (default).
  <p> Methods: <code> linearstep </code>: the linear time symbolic
  algorithm (default).

  </dl> ]

  SideEffects        []

  SeeAlso            [unset]

******************************************************************************/
static int
CommandSetVariable(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  char *flag_value, *key, *value;
  avl_generator *gen;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }
  if (argc == 0 || argc > 3) {
    goto usage ;
  }
  else if (argc == 1) {
    avl_foreach_item(cmdFlagTable, gen, AVL_FORWARD, &key, &value) {
      (void) fprintf(vis_stdout, "%s\t%s\n", key, value);
    }
    return 0;
  }
  else {
    key = argv[1];
    if (avl_delete(cmdFlagTable, &key, &value)) {
      FREE(key);
      FREE(value);
    }

    flag_value = argc == 2 ? util_strsav("") : util_strsav(argv[2]);

    (void) avl_insert(cmdFlagTable, util_strsav(argv[1]), flag_value);

    if (strcmp(argv[1], "vis_stdout") == 0) {
      if (vis_stdout != stdout) {
        (void) fclose(vis_stdout);
      }
      if (strcmp(flag_value, "") == 0) {
        flag_value = "-";
      }
      vis_stdout = Cmd_FileOpen(flag_value, "w", NIL(char *), 0);
      if (vis_stdout == NULL) {
        vis_stdout = stdout;
      }
#if HAVE_SETVBUF
      setvbuf(vis_stdout, (char *)NULL, _IOLBF, 0);
#endif
    }
    if (strcmp(argv[1], "vis_stderr") == 0) {
      if (vis_stderr != stderr) {
        (void) fclose(vis_stderr);
      }
      if (strcmp(flag_value, "") == 0) {
        flag_value = "-";
      }
      vis_stderr = Cmd_FileOpen(flag_value, "w", NIL(char *), 0);
      if (vis_stderr == NULL) {
        vis_stderr = stderr;
      }
#if HAVE_SETVBUF
      setvbuf(vis_stderr, (char *)NULL, _IOLBF, 0);
#endif
    }
    if (strcmp(argv[1], "history") == 0) {
      if (vis_historyFile != NIL(FILE)) {
        (void) fclose(vis_historyFile);
      }
      if (strcmp(flag_value, "") == 0) {
        vis_historyFile = NIL(FILE);
      }
      else {
        vis_historyFile = Cmd_FileOpen(flag_value, "w", NIL(char *), 0);
        if (vis_historyFile == NULL) {
          vis_historyFile = NIL(FILE);
        }
      }
    }
    return 0;
  }

  usage:
      (void) printf("usage: set [-h] [name] [value]\n");
      (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
      return 1;

}


/**Function********************************************************************

  Synopsis          [Implements the unset command.]

  CommandName       [unset]

  CommandSynopsis   [unset an environment variable]

  CommandArguments  [\[-h\] &lt;variables&gt;]

  CommandDescription [ A variable environment is maintained by the command
  interpreter.
  The "set" command sets a variable to a particular value, and the
  "unset" command removes the definition of a variable. <p>
  Command options:<p>
  </dl>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> &lt;variables&gt;
  <dd> Variables to be unset
  </dl>
  ]

  SideEffects        []

  SeeAlso            [set]

******************************************************************************/
static int
CommandUnsetVariable(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int i;
  char *key, *value;
  int c;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "h")) != EOF) {
    switch(c) {
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc < 2) {
    goto usage;
  }

  for(i = 1; i < argc; i++) {
    key = argv[i];
    if (avl_delete(cmdFlagTable, &key, &value)) {
      FREE(key);
      FREE(value);
    }
  }
  return 0;


  usage:
    (void) fprintf(vis_stderr, "usage: unset [-h] variables \n");
    (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");
    return 1;
}

/**Function********************************************************************

  Synopsis           [Implements the help command.]

  CommandName        [help]

  CommandSynopsis    [provide on-line information on commands]

  CommandArguments   [\[-a\] \[-h\] \[&lt;command&gt;\]]

  CommandDescription [Given no arguments, "help" prints a list of all commands
  known to the command interpreter.
  If a command name is given, detailed information for that command will be
  provided.<p>

  Command options:<p>
  <dl><dt> -a
  <dd> Provides a list of all internal commands, which by convention begin with an underscore.
  </dl>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>]

  SideEffects        []

******************************************************************************/
static int
CommandHelp(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int c, i, all;
  char *key;
  avl_generator *gen;
  char buffer[1024];
  char *command;
  char *lib_name;
#if HAVE_GETENV
  char *pager;
#endif


  util_getopt_reset();
  all = 0;
  while ((c = util_getopt(argc, argv, "ah")) != EOF) {
    switch(c) {
      case 'a':
        all = 1;
        break;
      case 'h':
        goto usage;
      default:
        goto usage;
    }
  }

  if (argc - util_optind == 0) {
    fprintf(vis_stderr,"List of commands:\n");
    i = 0;
    avl_foreach_item(cmdCommandTable, gen, AVL_FORWARD, &key, NIL(char *)) {
      if ((key[0] == '_') == all) {
        (void) fprintf(vis_stdout, "%-26s", key);
        if ((++i%3) == 0) {
          (void) fprintf(vis_stdout, "\n");
        }
      }
    }
    if ((i%3) != 0) {
      (void) fprintf(vis_stdout, "\n");
    }
  }
  else if (argc - util_optind == 1) {
    command = command_alias_help(argv[util_optind]);
    lib_name = Vm_VisObtainLibrary();
#if HAVE_GETENV
    pager = getenv("PAGER");
    if (pager != NULL) {
      (void) sprintf(buffer, "%s %s/help/%sCmd.txt", pager, lib_name, command);
    } else {
      (void) sprintf(buffer, "more %s/help/%sCmd.txt", lib_name, command);
    }
#else
    (void) sprintf(buffer, "more %s/help/%sCmd.txt", lib_name, command);
#endif
    (void) system(buffer);
    FREE(lib_name);
  }
  else {
    goto usage;
  }

  return 0;

usage:
  (void) fprintf(vis_stderr, "usage: help [-a] [-h] [command]\n");
  (void) fprintf(vis_stderr, "   -a \t\tprint help for all commands\n");
  (void) fprintf(vis_stderr, "   -h \t\tprint the command usage\n");

  return 1;
}

#if 0
Change "/*!*Function" to "/**Function" when reactivate command
/*!*Function********************************************************************

  Synopsis          [Implements the undo command.]

  CommandName       [undo]

  CommandSynopsis   [undo the result of the last command which changed the network]

  CommandDescription [ A simple 1-level undo is supported.
  It reverts the network to its state before the last command which
  changed the network.  Note that interrupting a command (with ^C)
  which changes the network uses up the one level of undo.<p> ]

  SideEffects        []

******************************************************************************/
static int
CommandUndo(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  if (argc != 1) {
    (void) fprintf(vis_stderr, "usage: undo\n");
    return 1;
  }

  (void) fprintf(vis_stderr, "** cmd error: undo: not yet implemented\n");
  return 1;

#if 0

  /*
   * FIX (Tom): can't enable "undo" until network_dup and hmgr_dup exist.
   */
  if (cmdBackupHmgr == NIL(Hrc_Manager_t)) {
    (void) fprintf(vis_stderr, "undo: no hmgr currently saved\n");
    return 1;
  }
  else {

    /* Swap the current and backup. */
    Hrc_Manager_t *temp = *hmgr;
    *hmgr = cmdBackupHmgr;
    cmdBackupHmgr = temp;
    return 0;
  }
#endif
}
#endif



/**Function********************************************************************

  Synopsis          [Implements the source command.]

  CommandName       [source]

  CommandSynopsis   [execute commands from a file]

  CommandArguments  [\[-h\] \[-p\] \[-s\] \[-x\] &lt;file&gt; \[&lt;args&gt;\]]

  CommandDescription [Reads and executes commands from a file.<p>
  Command options:<p>
  <dl><dt> -h
  <dd> Print the command usage.
  </dl>
  <dl><dt> -p
  <dd> Print a prompt before reading each command.
  </dl>
  <dl><dt> -s
  <dd> Silently
  ignore an attempt to execute commands from a nonexistent file.
  </dl>
  <dl><dt> -x
  <dd> Echo each command before it is executed.
  </dl>
  <dl><dt> &lt;file&gt;
  <dd> File name
  </dl>

  Arguments on the command line after the filename are remembered but not
  evaluated.  Commands in the script file can then refer to these arguments
  using the history substitution mechanism.<p>

  EXAMPLE:<p>

  Contents of test.scr:<p>

  <pre>
  read_blif_mv %:2
  init_verify
  simulate -n 10
  </pre>

  Typing "source test.scr lion.mv" on the command line will execute the
  sequence<p>

  <pre>
  read_blif_mv lion.mv
  init_verify
  simulate -n 10
  </pre>

  (In this case <code>%:0</code> gets "source", <code>%:1</code> gets
  "test.scr", and <code>%:2</code> gets "lion.mv".)
  If you type "alias st source test.scr" and then type "st lion.blif bozo",
  you will execute<p>

  <pre>
  read_blif_mv bozo
  init_verify
  simulate -n 10
  </pre>

  because "bozo" was the second argument on the last command line typed.  In
  other words, command substitution in a script file depends on how the script
  file was invoked. Switches passed to a command are also counted as
  positional parameters. Therefore, if you type "st -x lion.mv bozo",
  you will execute

  <pre>
  read_blif_mv lion.mv
  init_verify
  simulate -n 10
  </pre>

  To pass the "-x" switch (or any other switch) to "source" when the
  script uses positional parameters, you can define an alias. For
  instance, "alias srcx source -x".<p>


  ]

  SideEffects        [required]

  SeeAlso            [history]

******************************************************************************/
static int
CommandSource(
  Hrc_Manager_t ** hmgr,
  int  argc,
  char ** argv)
{
  int c, echo, prompt, silent, interactive, quit_count, lp_count;
  int status = 0; /* initialize so that lint doesn't complain */
  int lp_file_index, did_subst;
  char *prompt_string, *real_filename, line[MAX_STR], *command;
  FILE *fp;

  interactive = silent = prompt = echo = 0;

  util_getopt_reset();
  while ((c = util_getopt(argc, argv, "hipsx")) != EOF) {
    switch(c) {
        case 'h':
          goto usage ;
        case 'i':               /* a hack to distinguish EOF from stdin */
          interactive = 1;
          break;
        case 'p':
          prompt = 1;
          break;
        case 's':
          silent = 1;
          break;
        case 'x':
          echo = 1;
          break;
      default:
          goto usage;
    }
  }

  /* added to avoid core-dumping when no script file is specified */
  if (argc == util_optind){
    goto usage;
  }

  lp_file_index = util_optind;
  lp_count = 0;

  /*
   * FIX (Tom, 5/7/95):  I'm not sure what the purpose of this outer do loop
   * is. In particular, lp_file_index is never modified in the loop, so it
   * looks it would just read the same file over again.  Also, SIS had
   * lp_count initialized to -1, and hence, any file sourced by SIS (if -l or
   * -t options on "source" were used in SIS) would actually be executed
   * twice.
   */
  do {
    lp_count ++; /* increment the loop counter */

    fp = Cmd_FileOpen(argv[lp_file_index], "r", &real_filename, silent);
    if (fp == NULL) {
      FREE(real_filename);
      return ! silent;  /* error return if not silent */
    }

    quit_count = 0;
    do {
      if (prompt) {
        prompt_string = Cmd_FlagReadByName("prompt");
        if (prompt_string == NIL(char)) {
          prompt_string = "vis> ";
        }

      }
      else {
        prompt_string = NIL(char);
      }

      /* clear errors -- e.g., EOF reached from stdin */
      clearerr(fp);

      /* read another command line */
      if (CmdFgetsFilec(line, MAX_STR, fp, prompt_string) == NULL) {
        if (interactive) {
          if (quit_count++ < 5) {
            (void) fprintf(vis_stderr, "\nUse \"quit\" to leave VIS.\n");
            continue;
          }
          status = -1;          /* fake a 'quit' */
        }
        else {
          status = 0;           /* successful end of 'source' ; loop? */
        }
        break;
      }
      quit_count = 0;

      if (echo) {
        (void) fprintf(vis_stdout, "%s", line);
      }
      command = CmdHistorySubstitution(line, &did_subst);
      if (command == NIL(char)) {
        status = 1;
        break;
      }
      if (did_subst) {
        if (interactive) {
          (void) fprintf(stdout, "%s\n", command);
        }
      }
      if (command != line) {
        (void) strcpy(line, command);
      }
      if (interactive && *line != '\0') {
        array_insert_last(char *, vm_commandHistoryArray, util_strsav(line));
        if (vis_historyFile != NIL(FILE)) {
          (void) fprintf(vis_historyFile, "%s\n", line);
          (void) fflush(vis_historyFile);
        }
      }

      status = Cmd_CommandExecute(hmgr, line);
    } while (status == 0);

    if (fp != stdin) {
      if (status > 0) {
        (void) fprintf(vis_stderr, "** cmd error: aborting 'source %s'\n", real_filename);
      }
      (void) fclose(fp);
    }
    FREE(real_filename);

  } while ((status == 0) && (lp_count <= 0));

  return status;

usage:
  (void) fprintf(vis_stderr, "source [-h] [-p] [-s] [-x] file_name\n");
  (void) fprintf(vis_stderr, "\t-h print the command usage\n");
  (void) fprintf(vis_stderr, "\t-p supply prompt before reading each line\n");
  (void) fprintf(vis_stderr, "\t-s silently ignore nonexistent file\n");
  (void) fprintf(vis_stderr, "\t-x echo each line as it is executed\n");
  return 1;
}

/**Function********************************************************************

  Synopsis    [required]

  Description [optional]

  SideEffects [required]

  SeeAlso     [optional]

******************************************************************************/
static void
print_alias(
  char * value)
{
  int i;
  CmdAliasDescr_t *alias;

  alias = (CmdAliasDescr_t *) value;
  (void) fprintf(vis_stdout, "%s\t", alias->name);
  for(i = 0; i < alias->argc; i++) {
    (void) fprintf(vis_stdout, " %s", alias->argv[i]);
  }
  (void) fprintf(vis_stdout, "\n");
}


/**Function********************************************************************

  Synopsis    [required]

  Description [optional]

  SideEffects [required]

  SeeAlso     [optional]

******************************************************************************/
static char *
command_alias_help(
  char * command)
{
  char *value;
  CmdAliasDescr_t *alias;

  if (!avl_lookup(cmdAliasTable, command, &value)) {
    return command;
  }
  alias = (CmdAliasDescr_t *) value;
  return alias->argv[0];
}

/**Function********************************************************************

  Synopsis           [Function to flush vis_stdout and vis_stderr.]

  Description [This function is the signal handler for the SIGUSR1
  signal. Whenever that signal is received, this function is executed and the
  output channels of VIS are flushed.]

  SideEffects        []

  SeeAlso            [Cmd_Init]

******************************************************************************/
static void
FlushBuffers(
  int sigtype)
{
  fflush(vis_stdout);
  fflush(vis_stderr);

  /* Reprogram again the handler */
#ifdef SIGUSR1
  (void) signal(SIGUSR1, FlushBuffers);
#endif
} /* End of FlushBuffers */